Stuck in Park or Key stuck in ignition

02 Envoy SLE

I've recently purchased an 02 Envoy from an auction.

There are a couple of issues.
The main one started last night. While at the store I put the truck in park and turn off the ignition. The ignition will not go into the lock position. I messed with the key and go it to turn off. Then started the truck to leave and couldn't put the truck in gear. I messed with the shifter and was able to put into gear. At that point the gear shifter would move from park to reverse without me pushing the break pedal. I drove home and could not turn the key all of the way off again. Moved gear selector from 1st to Park a few times and then was able to remove the key. I restarted the truck and could not move the gear selector again; however I was able to remove the key easily.

I am leaning towards replacing the "Neutral Safety Switch" on the tranny but with my symptoms, I've seen brake light switch, ignition, and solenoid at gear shift selection. I'm just looking for a bit more guidance before doing the work.

Back up lights do not work either

Since I purchased the truck, I've replaced,
Battery
Ignition Coil

this has epl electronic park lock.2 solenoids.1 in the floor shifter compartment and one where the key lock cylinder is and is energized when in park and pin is retracted to remove key.the solenoid in the shifter compartment sometimes sticks and if you wiggle shifter and depress button it will free the key.if power is lost or voltage is not received at the solenoid at key cylinder or that solenoid or wiring is bad then key will not be able to be removed.a series of voltage checks would have to be done to isolate problem.i have a 2008 that sticks sometimes....i would like to diasable this permently.you should not be able to shift out of park without depressing brake pedal...that is the design.

I figured something out while messing around today. I can here the click when brake pedal is pressed. If I mess with shifter, mostly pushing it forward, I can get the shifter to move into gear. Moving from park to all gears is fine as long as I do not turn off the truck.
If I turn off the truck the key is stuck. If I push the break pedal and release I can turn the truck off.

try when key wont come out pushing the button on end of shifter and jiggling shifter.....if that helps take some wd40 and spray around end button.does this happen every time you shut off?

It just started happening everytime. When I first start the truck the button is difficult to depress. Moving the shifter stick forward makes it able to go into gear. When I am done driving and put it into park, try to turn off ignition and key is stuck. If I press the brake pedal again I am then able to turn the key off and remove it.

sound like the park lock actuator is sticking.when you press the brake pedal voltage is sent to the park lock actuator to energize and retract to allow you to shift.unless no voltage from stop lamp switch or adjustment issue.i use to have problems with mine when first bought it from truck sitting awhile before bought but has since stopped it.sometime i have to jiggle shifter end button or the shifter itself to get my key out.i am just assuming your design is similiar....but without a look at wiring diagram i dont know.i have all my wiring and diagnostic info which i got from alldatadiy.com.you would have to test circuit when it happens to isolate the problem.

this is some info on a 2002 blazer which should be similiar from alldata.....there is even a bypass procedure.

Automatic Transmission Shift Lock Control System
The automatic transmission shift lock control system is a safety device that prevents an inadvertent shift out of PARK when the engine is running. The driver must press the brake pedal before moving the shift lever out of the PARK position.
The system consists of the following components:


The automatic transmission shift lock control solenoid
The automatic transmission shift lock control switch With the ignition in the ON position, voltage is supplied to automatic transmission shift lock control switch. Voltage flows through the normally closed contacts of the automatic transmission shift lock control switch to the automatic transmission shift lock control solenoid. The automatic transmission shift lock control solenoid is permanently grounded. This energizes the automatic transmission shift lock control solenoid causing the transmission shift lever to be physically locked in the PARK position. When the brake pedal is pressed the contacts in the automatic transmission shift lock control switch open, de-energizing the automatic transmission shift lock control solenoid. This allows the shift lever to be move out of the PARK position.
Park Lock Solenoid
The park lock solenoid is a safety device that prevents an inadvertent shift out of PARK when the key is in the OFF position. The key must be in the RUN position to release the park lock solenoid.
The system consists of the park lock solenoid.
With the ignition in the ON position, voltage is supplied to the park lock solenoid. The park lock solenoid energizes through a permanent ground unlocking the shift lever. With the ignition in the OFF or ACCY position the park lock solenoid de-energizes and locks the shift lever in the park position

Shift Lock Bypass Procedure
In the event that service is required, a park lock solenoid manual release lever is located on the top right side of the floor shift assembly, under the shift lever trim boot. To operate the manual release lever, block the wheels and apply the parking brake. Lift the shift lever boot to expose the release lever. Push the release lever towards the front of the vehicle and move the shift lever to the neutral position.

Could be a bad BTSI solenoid, or the harness to it could have wires broken, but inside the insulation, causing intermittant contact....those wires do a lot of bending under the shifter....give a tug on each wire into the solenoid, and see if it breaks....

My money is on the wire harness...

I believe it is something in the wiring. I messed around with the wires at the brake switch at the brake pedal and haven't had the problem since. I'll keep monitoring and see where it goes.

Thanks for the help troubleshooting.

Usually not the wire harness at the brake switch, it the harness to the BTSI solenoid in the shifter.....over time, moving that shifter from park to drive and back, flexes those wires....done a ton of them in Grand Prix's....